Stepped Care for Posttraumatic Stress Disorder Study

This study uses a Sequential, Multiple Assignment, Randomized Trial (SMART) design. At baseline, participants are randomized to Stage 1 Treatments, either webSTAIR (self-managed) or webSTAIR plus community health worker coaching. At 8 weeks, stage 1 nonresponders are re-randomized to Stage 2 clinician-administered treatments, either Brief STAIR or WET. Nonresponse is defined as less than a 15-point decrease in PTSD symptom severity from baseline, as measured by the PTSD Checklist for DSM-5 (PCL-5). The objectives of this study are to: * examine the main effects of stage 1 treatments, stage 2 treatments, and embedded * adaptive interventions on PTSD symptom severity. * confirm mechanisms of change established in the extant PTSD literature * identify patient-level moderators of change in PTSD symptoms severity at 18 weeks